/**
  * Filter given wishlist collection
  *
  * @param Mage_Wishlist_Model_Resource_Wishlist_Collection $collection
  * @return Mage_Wishlist_Model_Resource_Wishlist_Collection
  */
 public function filterCollection(Mage_Wishlist_Model_Resource_Wishlist_Collection $collection)
 {
     $customer = Mage::getModel("customer/customer")->setWebsiteId(Mage::app()->getStore()->getWebsiteId())->loadByEmail($this->_email);
     $collection->filterByCustomer($customer);
     foreach ($collection as $item) {
         $item->setCustomer($customer);
     }
     return $collection;
 }